EXPERIMENTAL WORK WITH RAW ROCK PHOSPHATE. 91 



(south end) was limed and fertilized without manure, and sown to oats and 

 clover. Thenceforth the manure, lime, and fertilizers have all been applied to 

 the corn crops, the manure being plowed under and the lime and fertilizers 

 applied to the surface. The oats and clover receive no treatment. The clover 

 seeding failed in 1906, 1908, and 1909, and soy beans were grown instead and 

 harvested as hay. 



The plan of treatment, average yields per acre, for nine years, and 

 the increase per acre from the various treatments figured according 

 to the Ohio method and also by comparing each treatment with the 

 average of all the untreated plots are given in Table LV. 



The results obtained in 1914 and 1915 have been reported by 

 Thorne in Bulletin No. 305 of the Ohio station, but no yields are 

 given except those of the plots receiving acid phosphate and raw 

 rock. These last two years' results therefore are not included in the 

 averages given in Table LV. 



